Stands for "tenth of a ton", i.e. 200 pounds, and is used to refer to women of such size. There are also "over toats", which is , of course OVER 200 lbs. This term can be used freely and should replace BBW as a general term for overweight women. A BBW could be a TOAT, but not all TOATs are Big Beautiful Women.

" I no longer wondered why that Honda Civic scraped the ground pulling into Dairy Queen after I saw the two TOATS get out and rush the counter."

Queen Latifah is a BBW and probably a TOAT, but the fatty at Walmart in sweats and flip flops buying cigs, grape soda and circus peanuts is just a TOAT.

it's not certain exactely what the T stands for but rather cautiously, I can belive T being the first letter of a word.
The most likely source, most expert say. can be tittle.
In my opinion can also be Total.

(Nicky Santoro): "I would carry things out to a T".
"I will quote this to a T."
"This is total BS! to a T!"